rust: fix datatype in docs for `module` macro arguments

Remove the mention of byte array as datatype for `module` macro arguments
since the arguments are defined as string, and `alias` is a string array.

Signed-off-by: Aswin Unnikrishnan <aswinunni01@gmail.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240512112324.8514-2-aswinunni01@gmail.com


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>